Minimalism was the rallying cry at the University of Chicago’s new Mansueto Research Library. Chicago-based architecture firm Murphy/Jahn buried the book stacks—enough for 3.5 million volumes—in a cavernous subterranean vault and enclosed the only above-grade level, which houses a reading room, circulation desk, and book care facility, in a glass-encased steel grid shell structure. While the fritted glazing allows ample quantities of controlled natural light to flood the library during the day, at night an electrical lighting scheme was required. German lighting design firm Lichtplanung had to devise a way to implement an artificial lighting scheme within the space that would not mar the pristine quality of the architecture. “The challenge was to have a very simple and minimalistic solution,” explained Michael Rhode of Lichtplanung. “Helmut Jahn loves light, but he does not like to see light fixtures.”

Fulfilling the library’s lighting needs required both direct and indirect sources that could both fill the space with general illumination and also highlight certain areas. The design team at Lichtplanung had to study the architecture carefully in order to find places to discretely integrate luminaires. For the indirect lighting, the team settled on nesting their sources—low profile compact fluorescent fixtures—atop the ventilation kiosks that intersperse the reading room. From the top of the kiosks the lamps shine up to the roof of the grid shell. While black on its outward facing side, the glass’s fritting is grey on the interior side, creating a surface that captures the uplight and diffuses it throughout the space.

Task lamps were custom designed by the architects together with the desks (left). HIT spotlights proved highly efficient yet unobtrusive (right).

Direct lighting proved more of a challenge to the team since the clean lines of the grid shell structure didn’t offer any handy place to conceal fixtures. The only option, in fact, was to integrate the sources into the steel structural members. This meant choosing the smallest possible lamps with the highest possible output. The team selected HIT spotlights (tubular metal halide high intensity discharge lamps) outfitted with antiglare reflectors, which pump out an incredible 100 lumens per watt. The lamps range from 70 to 150 watts, with those closer to the floor of lower wattage and those towards the top of the dome of higher wattage.

These two sources provide all of the general illumination for the library. The team also implemented task lighting throughout the space, such as at the reading and circulation desks, where more focused light was needed.